 | WOOD ARKITEKTUR + DESIGN AS | 996454819 | OSLO |
| WOODSTOCK NATURLIGE BYGG AS | 826644222 | FROGN |
| WOODSTYLE AS | 925877115 | FROGN |
| WOODWORKS AS | 830176152 | INDRE ØSTFOLD |
| WORKINN AS | 966432578 | TROMSØ |
| WORKMAN AS | 997306503 | OSLO |
| WR MASKIN AS | 889195452 | ÅMOT |
| WS MASKIN OG EIENDOM AS | 932384027 | ASKØY |
| WS MASKIN & TRANSPORT AS | 984337647 | HARSTAD |
| WSP NORGE AS | 881894742 | OSLO |
| WWW.KONSTRUKSJON.COM TØRSET | 987032758 | SKAUN |
| X5 ELEKTRO AS | 979705883 | ALTA |
| X BETONG AS | 912156494 | ÅLESUND |
| XBO EIENDOMSUTVIKLING AS | 927716232 | STAVANGER |
| XFORM AS | 992186909 | SUNNFJORD |
| XK ENTREPRENØR AS | 995109409 | OSLO |
| XL-BYGG MATHISEN & CO AS | 997645359 | ALTA |
| XPERT INSTALLASJON AS | 981574036 | TØNSBERG |
| XPLAN AS | 934995260 | ÅLESUND |
| XTM DESIGN AS | 924119039 | ÅLESUND |
| XYLEM WATER SOLUTIONS NORGE AS | 918088067 | LILLESTRØM |
| YC AMUNDRUD AS | 925552550 | ELVERUM |
| YDSTEBØ BYGGTJENESTER AS | 914800919 | KVITSØY |
| YM CONSULT AS | 823242832 | OSLO |
| YMRO AS | 927210142 | OSLO |
| YOUNG AS | 990650705 | ÅLESUND |
| YRAN & DAHLE ARKITEKTER AS | 926515608 | OSLO |
| YR ARKITEKTER AS | 818946422 | BERGEN |
| YSSEN AS | 898803902 | LILLESTRØM |
| YTRELAND AS | 933731855 | KARMØY |
| YTTERDAHL AS | 929572912 | FARSUND |
| YTTERLI MASKIN AS | 829513722 | RAUMA |
| Z BYGG AS | 926177265 | LILLESTRØM |
| Z-CLIX AS | 930476749 | KRISTIANSAND |
| ZEINER BOLIG HÅNDVERK AS | 948974487 | FÆRDER |
| ZENITH ELEKTRO AS | 930349607 | SULA |
| ZEQIRI BYGG | 928642976 | GOL |
| ZIMM ARKITEKTER AS | 936027911 | OSLO |
| ZIS AS | 914876877 | FREDRIKSTAD |
| ZK ELEKTRO AS | 923399135 | FREDRIKSTAD |
| ZL BYGG AS | 924365935 | MELHUS |
| ZL MONTASJE AS | 924771747 | OSLO |
| ZM RØR AS | 998740533 | SURNADAL |
| ZYLA ADAM | 933766101 | ØSTRE TOTEN |